3 song CD player...

[rabbitz]

I've just bought a Sony CDPXE270 from eBay to use in a secondary system and is weird. Plays fine for the first few songs, about 15 minutes and then the sound becomes distorted and gets worse. Stop the player and let it sit for 10 minutes and all is well, so it could be heat related.

The distortion is similar to the sound you get when turning off an amp while music is playing and being fed by draining caps and also a bit like an FM station not tuned properly.

I've ordered a service manual and would appreciate any advise on directions or thoughts on this.

Initially I was looking at a power supply problem but the regs are putting out the right voltage and legs are intact. The supply to the op amp is not symmetrical with -14.25V and + 13V, but looks like it uses a virtual ground and this supply comes straight from the main caps after rectification.... not regulated so I'd say the smaller +ve value is due to other parts of the circuit running 5V and 7V via regs. I've been over the main board looking for bad solder joints.

The laser appears to be working OK as I put a toture CD through and plays tracks that a budget player normally does and tapping the chassis both vertical and horizontal doesn't induce skipping.

An ideas of where to start?

BTW, I'm not going to send it back as shipping is worth half the player price and you never know, I might learn something.

[Gasho]

Did you check , all other power supplyes?
Something is heatig up , and voltage is dropping.
Look at digital PS , that powering DAC,Filter.... It must be 5V+-.
You can try with cold spray . Open the machine , power it up , start play , and when player start to distord , spray one by one ,every active component (regulator, chips...)

You can buy Cold spray in every electronic shop.

[rabbitz]

Once again, thanks for your advice and I'll go get a can and give it a try.

Cheers